As for vehicle seats of automatic two wheeled vehicles and the like, vehicle seats made by cushion materials being placed on bottom plates and being covered with surface material are known (for example, see Patent Document 1).
The cushion material described in Patent Document 1 is a solid material and the under surface thereof is formed in a shape that corresponds to the shape of the upper surface of the bottom plate, the under surface of the cushion material being tightly in contact with the upper surface of the bottom plate.